CARYOPHYLLALES Juss. ex
Bercht. et J. Presl

Fossils There
are relatively few unambiguous fossils of
Caryophyllales. Fossil flowers with pantoporate pollen
grains and campylotropous ovules, but with segmented ovary, have
been found in Turonian layers.

Habit Usually
bisexual (sometimes monoecious, andromonoecious, gynomonoecious,
polygamomonoecious, dioecious, androdioecious, or gynodioecious),
usually perennial, biennial or annual herbs (sometimes evergreen
or deciduous trees, shrubs, suffrutices or lianas). Often leaf or
stem succulents. Often halophytes. Often with spines.
C4 or CAM (crassulacean acid metabolism) physiologies
often present as well as Kranz’ anatomy. Often mucilaginous.
Sometimes carnivorous.

Flowers Usually
actinomorphic (rarely zygomorphic). Hypanthium sometimes present.
Usually hypogyny (rarely half epigyny). Sepals (one to) five (to
23), usually with imbricate (sometimes valvate,
induplicate-valvate or open, rarely valvate-decussate, plicate or
descending-cochlear) aestivation, free or more or less connate.
Petals alt. petaloid staminodia (four or) five, with contorted or
imbricate aestivation, free, or absent. Nectaries/nectariferous
disc present at staminal bases or in tube formed by filament
bases and petal bases or on inner side of receptacle, or nectary
and disc absent.

Androecium
Stamens (one to) five to more than 4.000 (staminal primordia
usually five), in one or more whorls or in several groups (outer
stamens often initiated in pairs), antetepalous when stamens
isomerous relative to tepals; staminal development usually
centrifugal. Filaments free or more or less connate, sometimes
adnate to sepals or petals. Anthers basifixed or dorsifixed
(sometimes latrorse), versatile or non-versatile, usually
tetrasporangiate (rarely disporangiate), usually introrse
(sometimes extrorse), usually longicidal (dehiscing by
longitudinal slits; rarely poricidal, dehiscing by apical pores
or pore-like slits); outer parietal cells developing directly
into endothecium. Tapetum usually secretory (rarely
amoeboid-periplasmodial). Female flowers often with staminodia
(staminodia sometimes numerous in bisexual flowers). ‘Petaloids’
possibly in reality petaloid staminodia, developing
simultaneously as or after androecium (not prior to); petaloid
staminodia (’petals’) and ’antepetalous’ stamens possibly forming
a developmental unit.

Gynoecium Pistil
composed of (one or) two to five (to numerous) free or connate
carpels, carpel often open during development in
Polygonaceae and in “the betalain clade”
(Caryophyllales s.str.). Ovary superior, semi-inferior
or inferior, unilocular to multilocular; ovary sometimes with
subepidermal cell layer containing large amounts of
calciumoxalate. Stylodia two to five, free or more or less
connate, or style single, simple. Stigmas two to five, or stigma
one, capitate or lobate, papillate, Dry type. Pistillodium
usually absent (male flowers often with pistillodium).

Fruit Usually a
loculicidal and/or septicidal (rarely denticidal, circumscissile
or valvate) capsule (sometimes a nut or an irregularly dehiscing
capsule; rarely a berry, a berry-like fruit, a drupe, a
schizocarp or a syncarp), sometimes with persistent calyx. Bracts
and floral prophylls often partitioning in formation of dispersal
unit.

Potential synapomorphies of the
first main clade are according to Stevens (2001 onwards):
presence of pit glands; endosperm starchy; and presence of
acetogenic naphthoquinones. The first of the two subclades, “the
carnivorous clade”, has the topology
[[Droseraceae+Nepenthaceae]+[Drosophyllaceae+[Ancistrocladaceae+Dioncophyllaceae]]]
and is characterized by the following potential synapomorphies:
presence of vascularized multicellular glands; cymose
inflorescence; corolla with contorted aestivation; extrorse
anthers; unilocular ovary; and presence of plumbagin present. A
clade identified in some analyses has the topology
[Nepenthaceae+[Drosophyllaceae+[Ancistrocladaceae+Dioncophyllaceae]]]
and the synapomorphies: presence of fibriform vessel elements;
wood rays one or two cells wide; leaf vernation abaxially
circinate; petiole vascular bundles surrounded by massive
sclerenchymatous cylinder with embedded bundles; presence of wing
bundles; and basifixed anthers. Ancistrocladaceae and
Dioncophyllaceae share the following characters:
climbing woody habit; phellogen deeply seated; absence of
cortical vascular bundles; petiole with inverted vascular bundles
in sclerenchyma cylinder; actinocyclocytic stomata; introrse
anthers; and acetogenic naphthyl isoquinoline alkaloids
biosynthesized from polyketides (not from aromatic amino
acids).

The second main clade has the
topology
[Rhabdodendraceae+[Simmondsiaceae+[[Asteropeiaceae+Physenaceae]+[Macarthuriaceae+[Microteaceae+[[Caryophyllaceae+[Achatocarpaceae+Amaranthaceae]]+[Stegnospermataceae
to Cactaceae]]]]]]] and the potential synapomorphies
(Stevens 2001 onwards): filament much shorter than anther;
stylodia stigmatic (receptive) their entire length; ovules one or
two per carpel; fruit single-seeded; and endosperm sparse. This
clade minus Rhabdodendron is characterized by nodes 1:1
and absence of petals. Asteropeia and Physena
lack successive cambia; have a vascular cylinder in the young
stem; fibre tracheids; vasicentric tracheids; wood rays one or
two cells wide; aliform-confluent axial parenchyma; latrorse
anthers; and one-seeded fruit.

The core Caryophyllales
– “the betalain clade” – comprise
[Macarthuriaceae+[Microteaceae+[[Caryophyllaceae+[Achatocarpaceae+Amaranthaceae]]+[Stegnospermataceae
to Cactaceae]]]]. Hence, they include the caryophyllids
in the traditional strict sense. It is a group with very high
bootstrap support and characterized by a large number of
potential synapomorphies (Stevens 2001 onwards): herbaceous
habit; absence of normal secondary lateral growth; CAM
photosynthesis and C4 photosynthesis frequently
present; sieve tube plastids P-type, with a central angular
protein crystal surrounded by a ring of protein filaments;
absence of pericyclic fibres; cymose inflorescence; presence of
adaxial nectaries on stamen bases; pollen grains tricellular at
dispersal; exine with thin foot layer; median carpel adaxial;
ovary unilocular; stigmas papillate; placentation free central or
basal; ovules campylotropous; thickened exotestal and endotegmic
cells; endotegmic cells with bar-like thickenings; perisperm well
developed; absence of endosperm; starch grains clustered; embryo
curved and periferal; cotyledons incumbent; absence of
mitochondrial gene rps10; absence of plastid gene
rpl2 intron; ferulic acid ester-linked to unlignified
primary cell walls; presence of flavonols and
O-methylated flavonols, quinones, usually betalains
(chromoalkaloids) instead of anthocyanins, triterpenoid saponins
and phytoferritin; and absence of tannins and myricetin. Usually
phenylalanine-derived shikimic acid biosynthesis as starting
point for synthesis of benzylisoquinoline alkaloids and
betalains. An undifferentiated perianth evolved after the
separation of the Rhabdodendron lineage, and a
differentiated perianth may have originated at least nine times
(Brockington & al. 2009): Asteropeia,
Caryophyllaceae, Stegnosperma, species of
Limeum, Corbichonia,
Mesembryanthemoideae and Ruschioideae in
Aizoaceae, Mirabilis in Nyctaginaceae,
Glinus in Molluginaceae, Portulaca,
Didiereaceae, Basellaceae, and
Cactaceae.

The clade
[Caryophyllaceae+[Achatocarpaceae+Amaranthaceae]]
has the potential synapomorphies: stamens as many as tepals,
antetepalous; a single ovule; parietal tissue approx. four cell
layers thick; nucellar cap two to four cell layers thick;
especially outer exotestal cell walls thick, with stalactite-like
processes; mitochondrial genes rps1 and rps19
absent (lost); and often presence of phytoecdysteroids.

The lineages “above”
Stegnosperma are characterized by apotropous ovules.
“The globular inclusion clade” comprises Lophiocarpaceae
to Cactaceae and posesses sieve tube plastids with
globular crystalloids. The clade comprising
Sarcobataceae, Nyctaginaceae,
Agdestidaceae, Phytolaccaceae and
Petiveriaceae often forms an unresolved polytomy
(sometimes also including Gisekiaceae). It is
characterized by a single usually basal ovule per carpel;
similarities in ORF2280 sequence; and a 210 bp deletion in the
plastid genome. They have usually (Sarcobatus?) a
subepidermal phellogen; also paracytic stomata; and protein
bodies in the nucleus. This clade minus Nyctaginaceae
has racemose inflorescence and a baccate fruit.

The second large clade of “the
globular inclusion lineage” comprises Molluginaceae to
Cactaceae. The clade with the topology (Brockington
& al. 2013)
[[[Montiaceae+Halophytaceae]+[Didieraceae+Basellaceae]]+[Talinaceae+[Portulacaceae+[Anacampserotaceae+Cactaceae]]]]
(Portulacineae, of Nyffeler & Eggli 2010;
Cactineae of Ocamp & Columbus 2010) has the
following potential synapomorphies, according to Stevens (2001
onwards): succulent leaves and/or stem; normal secondary lateral
growth; phloem parenchyma cells with phytoferritin; stem
epidermis with calciumoxalate crystals; presence of mucilage
cells; leaves amphistomatic; median inner pair of floral
prophylls enclosing flower; hypogyny; petaloid tepals; median
tepal abaxial (opposite outer median floral prophyll); pollen
grains pantocolpate; absence of funicular obturator; and a six bp
deletion in plastid gene ndhF. The clade
[Talinaceae+[Portulacaceae+[Anacampserotaceae+Cactaceae]]]
is further characterized by columellae narrowed towards middle or
expanded towards base, sometimes fused; pollen grains with
granular internal surfaces; perforated foot layer; and very thin
non-apertural endexine (Nowicke 1996). Halophytaceae,
Basellaceae and Didiereaceae sometimes form a
monophyletic group, with Halophytum sister to the
remainder. Potential synapomorphies are ovary with a single basal
ovule; and a single-seeded indehiscent fruit.
Basellaceae may be sister-group to Didiereaceae
or even nested within that clade (Didiereaceae and
Basellaceae have often paracytic stomata). In this case,
Halophytum may be sister to Didiereaceae
including Basellaceae.

The monophyletic group
[Talinaceae+[Portulacaceae+[Anacampserotaceae+Cactaceae]]]
is supported by the potential synapomorphies (Stevens 2001
onwards): presence of mucilaginous cells; absence of pericyclic
fibres; leaves with axillary uniseriate, biseriate or
multiseriate hairs, bristles or scales; stomata parallelocytic
(stoma with a lateral series of at least three alternating
subsidiary cells increasing in size away from guard cells; also
present in Montiaceae); pericarp two-layered; fruit
covered by dry tepals; exocarp completely or almost caducous.
Portulacaceae and Cactaceae may be
sister-groups, according to Ocampo & Columbus (2010), using
data mainly from non-coding plastid DNA. Portulaca and
at least Pereskia share, e.g., a c. 500 bp deletion in
rbcL, and non-lignified parenchyma cells are sometimes
present in the wood in Portulaca and Cactaceae.
On the other hand, Nyffeler & Eggli (2010), using sequence
data from matK and ndhF, identified
Anacampserotaceae and Cactaceae as
sister-groups (they share among morphological features the
character of numerous stamens). A special arrangement of testa
cells along the dorsal juncture, presence of a dry aril and a
central field type of cuticular ornamentation are characteristic
features in several clades of Caryophyllales such as
Cactaceae and Portulacaceae (Barthlott
1984).

A characteristic feature of the
“ACPT clade” (Talinaceae, Portulaca,
Anacampserotaceae and Cactaceae) are the
non-vascularized hair-, bristle- or scale-like trichomes present
at the nodes in the leaf axils (sometimes on internodes or on the
lamina) (Ogburn & Edwards 2009). They arise from the
epidermis and are persistent. The hair-like trichomes are either
uniseriate or multiseriate (three or more cells in width). The
bristle-like trichomes are wide, flat and multiseriate (up to
more than 20 cells in width). The species in
Anacampseros sect. Avonia possess wide
scale-like trichomes which entirely surround the leaf distal to
the subtending leaf; these scales are apically lignified.
Bristle-like trichomes have been reported from species in
Anacampserotaceae, whereas hair-like trichomes are
present in Portulaca, Anacampserotaceae and
Cactaceae. Membranous, often paired, scale-like
trichomes are present in Talinum (Talinaceae).
They have often been interpreted as homologous with the axillary
trichomes, although they seem to be apices of vascularized
prophylls subsequently often developing into leaves (Ogburn &
Edwards 2009).

Problems concering homologies of
the perianth parts are notorious in Caryophyllales. A
uniseriate perianth is most probably plesiomorphic in
Caryophyllales, and the uniseriate floral organs may be
homologous (Brockington & al. 2009). A perianth may have
originated by formation of homologous organs (perhaps in most
lineages of Caryophyllales), or by differentiation of
structures derived either from the androecium (in
Corbichonia in Lophiocarpaceae, in the
[Mesembryanthemoideae+Ruschioideae] clade of
Aizoaceae, and in Molluginaceae) or from bracts
(in Nyctaginaceae and in the “ACPT” clade), whereas
‘petaloid staminodia’ refer to floral parts that are
anambiguously derived from the androecium. The terms ‘sepaloid
tepals’ and ‘petaloid tepals’ are applied to floral organs (with
quincuncial-imbricate aestivation) present in the core clade of
Caryophyllales (Brockington & al. 2009). ‘Petaloid
tepals’ in Caryophyllaceae, Stegnosperma, and
Limeaceae have often been interpreted as modified
stamens (e.g. Ronse De Craene 2007, 2008, etc.).

Distribution
Arid tropical and subtropical regions including western and
southern Australia, with their highest diversity in southern and
southwestern Africa. Mesembryanthemoideae and, above
all, Ruschioideae dominate much of the succulent
vegetation in the Karroo areas of South Africa, where they
constitute more than half the number of species and more than 90%
of the biomass.

Fossils
Unknown.

Habit Usually
bisexual (rarely monoecious or dioecious), perennial or annual
herbs (rarely climbing), suffrutices or shrubs. Usually leaf
succulents (sometimes stem succulents, rarely root succulents;
some species are almost entirely subterranean). Almost all
representatives are xerophytes; some species are halophytes.
C4 or CAM (rarely C3) physiology present.
Kranz’ anatomy present in some species. Usually mucilaginous.

Androecium
Stamens usually numerous (to more than 2.000; sometimes four,
five, eight, or ten), in one or more whorls or in three to nine
groups; staminal primordia five, alternitepalous, or as annular
meristem. Outer whorls usually consisting of petaloid staminodia,
inner whorls consisting of fertile stamens, median whorls often
intermediary. Filaments free or connate (all or in three to nine
groups), free from tepals. Anthers dorsifixed, often versatile,
tetrasporangiate, introrse, longicidal (dehiscing by longitudinal
slits). Tapetum secretory, with usually trinucleate (rarely
septanucleate) cells. Staminodia petaloid, extrastaminal, usually
numerous (absent in some genera).

Fruit Usually a
loculicidal capsule (sometimes a nut, rarely a pyxidium, a berry
or a schizocarp; in Gunniopsis a septicidal capsule),
usually hydrochastic, dehiscing in moist weather, when septa and
other tissues swell (septal keels, reaching from central axis to
valve apices).

Apatesieae are
sister-group to the clade
[Dorotheantheae+[Delospermeae+Ruschieae]]
and possess an annular holonectary. The capsule often lack
hygrochastic properties and has very reduced expanding keels.
The clade
[Dorotheantheae+[Delospermeae+Ruschieae]]
has a covering membrane. Dorotheantheae are annual
herbs with semi-succulent leaves. The nectar is a wide and flat
meronectary. The [Delospermeae+Ruschieae]
clade has a lophomorphic nectary and a hygrochastic capsule.
Moreover, the intron of the plastid gene rpoC1 is
absent (lost). Delospermeae have a lophomorphic
meronectary. Ruschieae have a lophomorphic holonectary
and the nuclear gene ARP (a leaf developmental gene)
is often duplicated (absent in some species).

Flowers
Actinomorphic, small. Usually hypogyny (rarely half epigyny).
Tepals (one or) three to five (to eight), with usually imbricate
(rarely valvate) aestivation, sepaloid, often fleshy, often with
tuberculate, spinulose or wing-like outgrowths, persistent, free
or connate at base, or rudimentary or absent. Nectary absent.
Disc (sometimes lobate) present in some species.

Androecium
Stamens (one or) five (to nine), usually as many as sepals,
antesepalous, or absent. Filaments free or connate in lower part
(sometimes entirely) into a tube, often adnate to tepals
(epitepalous); tuberculate, scale-like or fringed
staminodium-like lobes, pseudostaminodia, often present between
stamens and usually fused with filaments. Anthers usually
dorsifixed, often versatile, usually tetrasporangiate (sometimes
disporangiate), usually introrse (rarely extrorse), longicidal
(dehiscing by longitudinal slits); connective sometimes with
apical appendage (sometimes vesicular and coloured); anther wall
development monocotyledonous. Tapetum usually secretory, with
binucleate or multinucleate cells (sometimes
amoeboid-periplasmodial). Staminodia one to five, often petaloid,
or absent.

Gynoecium Pistil
composed of (one or) two or three (to six) connate carpels
(median carpel sometimes abaxial); when two carpels then usually
transverse. Ovary usually superior (rarely semi-inferior),
unilocular. Style single, simple, or stylodia two or three, long
or short, more or less connate. Stigma one, capitate (simple or
penicillate), or stigmas two or three (to six), narrowly
elongate, papillate, Dry type, often persistent. Pistillodium
usually absent (male flowers sometimes with pistillodium).

Fruit Usually a
nut (often a utriculus or an achene) or an irregularly dehiscent
capsule (often a pyxidium, rarely a berry, a baccaceous fruit or
a drupe; adjacent ovaries sometimes fusing and forming a
syncarp), often surrounded by more or less fleshy perianth
forming an anthocarp; persistent and often accrescent bracts and
floral prophylls sometimes forming parts of dispersal unit.

Fruit A
loculicidal and/or septicidal capsule dehiscing from apex into
three or six valves, with caducous exocarp usually separating
from endocarp (not in Grahamia). Perianth remnants and
stamens persistent and forming a dry calyptra (Grahamia,
Talinopsis) or caducous (Anacampseros).
Endocarp valves forming small basket.

Distribution
Mainly arid and semiarid regions of North and South America
(British Columbia and Alberta southwards to Patagonia); also
epiphytes and lianas in rain forests and other moist forests
(Rhipsalis also in tropical Africa, Madagascar, the
Seychelles, the Mascarenes and Sri Lanka, possibly
introduced?).

Habit Usually
bisexual (at least in Mammillaria dioica and
Selenicereus innesii functionally dioecious), usually
perennial herbs (sometimes climbing or epiphytic; rarely
deciduous shrubs or small trees [Rhodocactus,
Pereskia]). Usually xerophytic. Almost all species are
stem succulents with elongate and branched or unbranched, or
almost globular pachycaul photosynthesizing stem; some genera
with flattened almost foliaceous stem segments, phylloclades.
Stem and branch surfaces usually with areolae – modified axillary
short shoots, brachyblasts – with numerous spines – modified
leaves or foliar lobes.

Flowers Usually
actinomorphic (rarely zygomorphic, e.g. Schlumbergera,
Zygocactus), often large. Usually epigyny (rarely half
epigyny or hypogyny). Hypanthium present or absent. Tepals few to
many, spiral, with imbricate aestivation (Rhodocactus,
Pereskia), usually petaloid, free or connate into
perianth tube, downwards grading via sepaloid tepals and tepaloid
bracts into scale-like bracts. Nectariferous disc (in, e.g.,
Pereskia and Rhipsalis) or nectaries at base of
hypanthium and androecium (in some species of Opuntia on
annular or cupular outgrowth at stylar base).

Androecium
Stamens c. 20 to more than 4.000, usually at least initially
spiral, later often in one or two whorls, or more than perianth
tube length (staminal primordia initiated in fascicles and often
continuing tepal spiral phyllotaxis). Androecial ring primordium
sometimes present. Filaments free, usually adnate to perianth
tube. Anthers basifixed or dorsifixed, sometimes versatile,
tetrasporangiate, introrse, longicidal (dehiscing by longitudinal
slits). Tapetum secretory. Staminodia present in some genera.

Gynoecium:
Pistil composed of three to more than 20 connate carpels. Ovary
usually inferior (in Pereskia superior or
semi-inferior), usually unilocular (sometimes partially
multilocular due to secondary septa). Style usually single,
simple, long. Stigma trilobate to more than 20-lobate,
non-papillate, Wet type. Pistillodium usually absent.

The generic and specific
delimitations are notorious in Cactaceae. Hence, the
species numbers within the genera are often highly
provisional.

Cactaceae have
undergone a tremendous increase in number of perianth parts as
compared to their closest relatives
(Anacampserotaceae, Portulacaceae,
Talinaceae, Basellaceae,
Didiereaceae and Halophytaceae). The spirally
arranged perianth parts in Cactaceae may be bracteal
rather than staminodial in their homology (Ronse De Craene
2007, 2008, etc.). The perianth may have evolved through
differentiation and inclusion of supernumerary bracts (Ronse De
Craene 2008) or through development of additional bracts.
Brockington & al. (2009) suggest that this increase in
perianth parts may be partially the result of a corresponding
increase in meristem size and merosity of reproductive
organs.

The subdivision of
Opuntioideae and Cactoideae are according to
Nyffeler & Eggli (2010c).

Distribution
Cosmopolitan although mainly temperate regions in the Northern
Hemisphere, the Arctic, temperate parts of the Southern
Hemisphere (including the Antarctic continent), tropical
mountains, with their largest diversity in the Mediterranean and
West and Central Asia.

Fossils The
fossilized inflorescence of Caryophylloflora paleogenica
from Tasmania has been assigned to Caryophyllaceae.
Fossil pollen grains, Caryophyllidites polyoratus, are
described from the Oligocene of New Zealand, and similar pollen
fossils have been found in the Miocene onwards of Europe.

Flowers
Actinomorphic. Epicalyx consisting of one or more pairs of floral
prophylls (bracteoles) sometimes present. Anthophore (prolonged
internode between sepal and ovary, and between petals and
stamens) sometimes present. Usually hypogyny (rarely perigyny).
Sepals (three to) five (to 23), usually with imbricate (rarely
valvate) aestivation, free or more or less connate. Petals
(petaloid staminodia?) usually five (sometimes four), with
usually contorted (rarely imbricate) aestivation, free, often
bifid and/or clawed (sometimes fimbriate), often with a
scale-like appendage, ‘corona’, in transition zone between claw
and limb (‘petals’ sometimes absent); ‘corona’(in, e.g.,
Silene) arising from two bulges on adaxial side of
’petals’ (possibly former staminal thecae). Nectariferous disc at
staminal bases or in tube formed by filament bases and petal
bases or on inner side of a cupular receptacle (and sometimes
nectar glands on abaxial side of base of episepalous
stamens).

Androecium
Stamens usually five or 5+5 (rarely one to five or more than
ten), in one or two whorls, usually haplostemonous or
diplostemonous (rarely 15, obdiplostemonous), usually
antesepalous (rarely alternisepalous). Filaments connate at base
or free from each other, often adnate to tepals (epitepalous).
Anthers usually dorsifixed, versatile, tetrasporangiate,
introrse, longicidal (dehiscing by longitudinal slits). Outer
secondary parietal cell dividing. Tapetum secretory, with
binucleate or multinucleate cells. Female flowers often with
staminodia.

Gynoecium Pistil
usually composed of two to five (to ten) connate antepetalous or
antesepalous carpels, sometimes with gynophores; when three
carpels then odd carpel adaxial. Ovary usually superior (rarely
semi-inferior), unilocular (below and/or as young sometimes bi-
to quinquelocular). Stylodia two to five, usually filiform,
usually free (sometimes connate in lower part). Stigmatic area
along entire or part of adaxial side of style or only at apex,
papillate, Dry type. Male flowers often with pistillodium.

The petals have possibly
androecial origin (see, e.g., Ronse De Craene & al. 1998,
Ronse De Craene 2007 and 2008). However, it is ambiguous
whether the absence of petals is ancestral or whether loss of
petals have occurred several times in
Caryophyllaceae.

The subdivision below follows
Harbaugh & al. (2010) and Greenberg & Donoghue (2011),
although it is still under construction (many generic names
unplaced). The descriptions of the clades are mainly according
to Stephens and Harbaugh & al. (2010).

Habit Bisexual
(Calyptrotheca, Portulacaria) or dioecious (in
Ceraria and Decaryia rarely gynodioecious),
evergreen or deciduous trees or shrubs (rarely climbing). Many
species are cactus-like xerophytic stem succulents, often with
short shoots (brachyblasts) modified into a small and definite
number of spines.

Androecium
Stamens four or five, in one whorl, alternitepalous, or seven to
numerous (in Calyptrotheca up to c. 60), in several
whorls; developed from annular primordium. Filaments free or
connate at base into ring of adaxial nectaries, usually free from
tepals (in Portulacaria adnate to sepals, episepalous).
Anthers dorsifixed, often versatile, tetrasporangiate, introrse,
longicidal (dehiscing by longitudinal slits). Tapetum secretory?
Female flowers sometimes with staminodia.

Fruit Usually a
one-seeded achene (in some groups enclosed inside two dry
sepaloid bracteoles; in Ceraria a samara; dehiscence in
Calyptrotheca circumscissile at base and splitting
upwards into valves in upper part, with strongly accrescent
calyx).

Trichomes
Glandular hairs multicellular, insensitive, stalked or sessile,
secreting a viscous mucilage with and without proteolytic
enzymes, respectively. Glandular heads in Triphyophyllum
consisting of two layers of secretory cells and inside these
layers an endodermis; glandular stalk usually vascularized (xylem
and phloem).

The young leaves in
Triphyophyllum resemble those in
Drosophyllum: circinate and insectivorous. The
carnivorous habit is lost in Dioncophyllum and
Habropetalum, or in their common ancestor. A cladistic
treatment of Dioncophyllaceae is needed in order to
answer this question.

Distribution
Cosmopolitan except polar and arid regions, with their largest
species diversity in Australia and New Zealand.

Fossils Seeds
assigned to Aldrovanda (c. fossil 20 species described)
have been found in the Oligocene and the Miocene of Siberia and
the Eocene of Europe. Some cenozoic pollen grains assigned to
Droseraceae have been described under the name of
Saxonipollis. Fossil pollen of Drosera have
been reported from the Miocene of New Zealand and Europe.

Habit Bisexual,
perennial or annual herbs (in Drosera sometimes
climbing). Corm or tuberous rhizome present in some species of
Drosera. Most species are hygrophytes;
Aldrovanda is aquatic with submersed leaves.
Carnivorous; Aldrovanda: ‘snaptraps’ with c. 20 trigger
hairs per foliar lobe; Dionaea: ‘snaptraps’ with three
trigger hairs per foliar lobe; Drosera: ‘flypaper
traps’.

Leaves Opposite,
simple, entire, linear, often ericoid, with ? ptyxis. Stipules
absent; leaves in each pair fused by a common sheath. Petiole
vascular bundles? Leaf single-veined. Stomata usually anomocytic
(sometimes paracytic). Cuticular wax crystalloids absent.
Mesophyll often with sclerenchymatous idioblasts in association
with vascular strands. Epidermis often with salt-secreting glands
(consisting of six crescent cells in two layers of three). Leaf
margin entire, usually reflexed.

Inflorescence
Terminal or axillary, cymose of various shapes, or flowers
solitary axillary.

Flowers
Actinomorphic, small. Hypogyny. Sepals usually five (sometimes
four, six or seven), with induplicate-valvate aestivation,
persistent, usually connate into a tube (calyx in Frankenia
triandra campanulate or urceolate). Petals usually five
(sometimes four, six or seven), with imbricate aestivation,
clawed, usually with adaxial scale-like appendage, ligule, with
nectary on stipe, free. Disc absent.

SystematicsFrankenia (c 70; subtropical and warm-temperate dry
regions (especially on sea-shores) in southern Europe,
northernmost and southernmost Africa, Macaronesia, the
Mediterranean, southwestern Asia and Australia, St. Helena,
southwestern North America, southwestern South America, with
their largest diversity in Australia).

SystematicsGisekia (7; tropical and subtropical regions in
Africa, Madagascar, the Mascarene Islands, South Asia eastwards
to southeastern China and Indochina, with their highest
diversity in East Africa).

Inflorescence
Male flowers numerous in a terminal, dense, spike-like, bracteate
inflorescence. Female flowers four or five together in axillary
fascicles (or female flowers in reality solitary axillary?) in
uppermost four or five leaf axils. Male flowers with two bracts
or floral prophylls (bracteoles; transverse floral prophylls
absent). Each female flower sunken into cortex and enclosed by
one (or two?) small bracts and two very unequally sized median?
floral prophylls.

The genus comprises all the
former species of Hypertelis except the type
Hypertelisspergulacea, which was shown to be
nested inside Molluginaceae (in the polyphyletic
‘Mollugo’; Christin & al. 2011; Christenhusz &
al. 2014).

Gynoecium Pistil
composed of two to seven connate antesepalous carpels. Ovary
superior, pseudomonomerous, two carpels being initiated: adaxial
carpel sterile and much smaller than abaxial carpel, in which two
ovules are developed and separated by secondary septum. Stylodia
two or three or absent. Stigmas two or three, filiform, type?
Pistillodium absent.

Gynoecium Pistil
composed of three to seven connate antesepalous carpels. Ovary
superior, with two carpels initiated: adaxial carpel sterile and
much smaller than abaxial carpel, in which two ovules develop and
are separated by secondary septum. Stylodia two or three or
absent. Stigmas two or three, filiform, type? Pistillodium
absent.

Inflorescence
Terminal or seemingly leaf-opposite, thyrsoid, with racemes or
spikes arranged in groups of usually three (sometimes two)
partial inflorescences. Floral prophylls (bracteoles two or
absent).

Gynoecium Pistil
composed of two to four connate carpels (with various
orientation). Ovary superior, unilocular (without traces of a
suture). Stylodia three to five. Stigmas three to five,
papillate, type? Pistillodium absent.

Androecium
Stamens (two to) four to ten (to c. 30, in fascicles),
diplostemonous, usually antetepalous (in Polpoda
alternitepalous) or – when more than five – in alternitepalous
and epitepalous whorls. Filaments widened at base and usually
connate into a tube, free from tepals. Anthers basifixed or
dorsifixed, often versatile, tetrasporangiate, introrse,
longicidal (dehiscing by longitudinal slits). Tapetum secretory.
Staminodia petaloid or absent.

Distribution
Cosmopolitan except polar areas (mainly temperate regions on the
Northern Hemisphere), Australia, Tasmania, New Zealand,
Kerguélen, North and South America, with their largest diversity
in western North America, western South America and southern
Australia.

Inflorescence
Terminal or axillary, dichasia and/or monochasia (sometimes
head-, spike or raceme-like), often scorpioid, or flowers
solitary axillary. Floral prophylls (bracteoles) usually two or
2+2 (inner pair median; rarely three, up to nine
[Lewisia] or absent), with imbricate aestivation,
lateral, apical or basal, at equal or different heights, usually
persistent and dry in fruit, free or connate at base (transverse
floral prophylls sometimes absent). Montiopsis sometimes
with trilobate involucral bracts.

Flowers Usually
actinomorphic (rarely zygomorphic). Hypogyny. Tepals (two or)
three to five (to seven; in Lewisia up to 19), in one or
two whorls, with imbricate aestivation, petaloid, persistent or
caducous, usually free (rarely connate at base), or absent.
Nectariferous disc present.

Androecium
Stamens usually three to five (rarely six, seven or up to c. 100;
in Lewisia up to 19; in
Calandrinia/Monocosmia and
Calyptridium one), in one whorl, usually antetepalous
(in Lyallia alternitepalous). Filaments free or connate
(all together or in fascicles), free from tepals or adnate at
base. Anthers dorsifixed, versatile, tetrasporangiate, introrse,
longicidal (dehiscing by longitudinal slits). Tapetum secretory,
with multinucleate cells. Staminodia usually absent.

Phemeranthus is sister
(with high support) to the remaining genera in the
ndhF analysis by Applequist & Wallace (2001).
Claytonia has tricolpate pollen grains, whereas its
sister-group Montia has pantocolpate pollen.

Phylogeny (simplified) of
Montiaceae based on DNA sequence data
(Applequist & Wallace 2001). Baitaria,
Lyallia, Parakeelya, and
Philippiamra were not included in the study.
Lyallia is sister to the
[Lewisia+[Montia+Claytonia]]
clade in analyses by Ogburn & Edwards (2009).

Fossils Fossil
pollen grains, which may be assigned to Nepenthes, have
been found in Late Cretaceous layers in South America and Africa,
and in the Eocene and the Miocene of Europe.

Habit Dioecious,
usually scrambling and climbing (sometimes epiphytic) perennial
herbs (rarely lignified). Carnivorous (largely utilizing
excrements and other detrimental waste products from animals
living in the water solution of the pitcher and feeding on prey
falling into the pitcher). Often hygrophytes.

SystematicsNepenthes (90–140; Madagascar, the Seychelles, Sri
Lanka, Assam, Southeast Asia, southeastern China, Malesia, New
Guinea, Queensland, New Caledonia, with their largest diversity
in West Malesia and the Philippines).

Distribution
Tropical, subtropical and warm-temperate regions in the Northern
and Southern Hemispheres, with their largest diversity in North
and South America; Phaeoptilum in southwestern
Africa.

Fossils Pollen
grains assigned to Nyctaginaceae have been found in
Eocene layers in Argentina, and the Late Campanian
Retitricolpites multibaculates from the island of
Sakhalin in Russia also resemble nyctaginaceous pollen.

Habit Usually
bisexual (rarely monoecious, andromonoecious, gynomonoecious or
dioecious), evergreen or deciduous trees (Leucastereae),
shrubs or lianas, perennial or annual herbs. Roots sometimes
fleshy or tuberous. Band-shaped sticky secretions present on
internodes in Anulocaulis, Cyphomeris, and some
species of Boerhavia.

Inflorescence
Terminal or axillary, panicle, spike- or umbel-like etc., or
flowers solitary axillary. Partial inflorescences or single
flowers often in pseudanthia, surrounded by free or connate
sepaloid or petaloid bracts forming an involucre.

Flowers Usually
actinomorphic (in species of Colignonia and
Allionia zygomorphic). Hypogyny. Tepals (three or) four
or five (to seven), in a single whorl, with induplicate-valvate
or contorted (plicate?) aestivation, usually petaloid, with lower
part usually carnose or coriaceous, connate into a tube or
infundibuliform to campanulate, with upper part usually early
caducous and lower part usually persistent around fruit. Nectary
usually absent (sometimes present on receptacle). Disc present
(often annular and enclosing ovary) or absent.

Androecium
Stamens one to ten (to c. 40), in one or sometimes two whorls,
usually alternisepalous. Filaments usually connate at base (in
Leucastereae free), usually free from tepals. Anthers
basifixed to dorsifixed, often versatile, tetrasporangiate,
latrorse or partially introrse, longicidal (dehiscing by
longitudinal slits). Tapetum secretory, with binucleate cells.
Female flowers in Pisonieae with staminodia.

Pollen grains
Microsporogenesis simultaneous. Pollen grains 3(–4)-colpate
(Leucastereae), 6–18-pantocolpate (Belemia,
Phaeoptilum) or polypantoporate (some species with
twelve to numerous pores), shed as monads, tricellular at
dispersal. Some species (e.g. in Mirabilis) with pollen
grains having a diameter of at least 200 μm (some of the largest
among angiosperms). Exine tectate or semitectate, with
columellate infratectum, reticulate or punctate to anulopunctate,
spinulate, echinate or tegillate.

Flowers Usually
actinomorphic (in Hilleria somewhat zygomorphic), small.
Usually hypogyny (rarely epigyny or half epigyny). Tepals in
various numbers, usually four (in Monococcus and
Petiveria four diagonal, in Seguieria five
orthogonal), with imbricate aestivation, sepaloid, whorled,
usually persistent, usually free (in Hilleria three
tepals somewhat connate). Nectary absent. Disc absent.

Androecium
Stamens four to c. 65 (in Rivina four, in
Hilleria four to 13, in Seguieria up to c. 65),
in one or two whorls. Filaments free or somewhat connate at base,
free from tepals. Anthers dorsifixed, sometimes versatile,
tetrasporangiate, introrse or extrorse, longicidal (dehiscing by
longitudinal slits). Tapetum secretory. Female flowers in
Ledenbergia with four to six staminodia.

Fruit A
one-seeded berry (Rivina, Trichostigma), a
nutlet (in Petiveria with bristle-like processes) or a
samara (in Seguieria and Gallesia with enlarged
persistent lignified sepals; in Schindleria,
Ledenbergia and Hilleria a utriculus; in
Ledenbergia with wing-like sepals). Pericarp usually
adnate to seed.

Petiveriaceae have
generally been included in Phytolaccaceae, but differ
from the latter clade by usually having a single carpel and by
the shape of its calciumoxalate crystals, and possibly by a
number of chemical features, although the phytochemistry of
this group is poorly known.

Distribution
Tropical and subtropical regions, with their largest diversity in
South America.

Fossils
Unknown.

Habit Usually
bisexual (rarely dioecious), evergreen trees, shrubs or lianas
(Ercilla), perennial or annual herbs
(Anisomeria is a succulent). Anisomeria and
some species of Phytolacca with napiform roots.

Gynoecium
Carpels three to 16, seemingly or secondarily free or connate
below and with free stylodia (carpels in Nowickea on
gynophore), initiated in a ring around receptacular apex,
alternitepalous or antetepalous. Ovary single, superior,
unilocular (pseudapocarpy). Stylodia three to 16, free or
connate, more or less gynobasic. Stigmas free, type? Male flowers
sometimes with pistillodium.

Flowers
Actinomorphic. Hypogyny. Sepals five, with valvate or plicate
aestivation, persistent, often membranous or petaloid, with five
or ten ridges, usually connate into a tube (rarely free). Petals
five, with usually contorted (sometimes imbricate) aestivation,
often persistent, connate usually only at base (sometimes
entirely), in Aegialitis coriaceous; petal and staminal
primordia common. Nectaries often present (sometimes as five
glands alternating with stamens). Disc absent.

Trichomes Hairs
unicellular or multicellular, usually uniseriate (sometimes
stellate or glandular, also peltate-lepidote).

Leaves Usually
alternate (spiral; rarely opposite or verticillate), usually
simple (rarely pinnately compound), entire or lobate, sometimes
fleshy or coriaceous (in Muehlenbeckia and
Calligonum rudimentary), usually with revolute (in
Muehlenbeckia convolute) ptyxis. Stipules usually
enclosing stem as a caducous or persistent, membranous, often
lobate or fimbriate tubular ocrea (usually absent in the
Eriogonum clade; rudimentary in some species of
Chorizanthe). Colleters present in association with
leaves. Foliar tendrils present in Antigonon. Petiole
vascular bundle transection usually annular (sometimes D-shaped;
bundles scattered in some species of Coccoloba).
Extrafloral nectaries present in some species on abaxial side of
petiolar pulvinus. Venation pinnate or palmate. Stomata usually
anomocytic (rarely diacytic, anisocytic, helicocytic, or
paracytic). Cuticular wax crystalloids as platelets or rodlets.
Lamina sometimes gland-dotted. Epidermis often with mucilage
cells. Leaf margin usually entire (sometimes crenate or
lobed).

Inflorescence
Usually terminal or axillary, simple or compound panicle,
thyrsoid, or spike-, head- or raceme-like (flowers rarely single
axillary). Each flower usually subtended by a persistent
membranous, tubular ocreola consisting of two connate floral
prophylls (bracteoles). Partial inflorescence in the
Eriogonum clade surrounded by and partially enclosed by
involucrum.

Fruit A usually
triangular (rarely lenticulate) achene, sometimes winged or with
bristles (rarely a berry), often surrounded by persistent and
sometimes accrescent tepals (in Emex and
Oxygonum surrounded by receptacle/hypanthium).

Symmeria and
Afrobrunnichia are successive sister-groups to the
remaining analysed genera of Polygonaceae, which are
subdivided into a mostly ligneous clade (with, e.g., the
Eriogonum group) and a mainly herbaceous clade.

Fruit Usually a
loculicidal valvicidal capsule (dehiscent from apex and/or base),
often with caducous exocarp separating from fibrous persistent
endocarp (capsule in ‘Talinella’ berry-like, juicy and
mucilaginous; capsule in Amphipetalum a pyxidium,
opening by a circumscissile operculum). Pericarp epidermis
papillate. Capsule covered by dry remnants of perianth, stamens
and style, these shed together as a calyptra.

Distribution
Mostly drier regions of northern, northeastern and southwestern
Africa, and Eurasia eastwards to East Asia, with their largest
diversity in the Mediterranean and the irano-turanian areas;
naturalized in North America.

Fossils Fossil
wood of Tamarix has been found in Pleistocene (possibly
also Pliocene) layers in North Africa.

Flowers
Actinomorphic, usually small. Hypogyny. Sepals four or five (or
six), with imbricate aestivation, persistent, usually free (in
Reaumuria connate below). Petals four or five (or six),
with usually imbricate (in Reaumuria contorted)
aestivation, persistent or caducous, usually without scale-like
appendage (in Reaumuria two adaxial scale-like
appendages at petal base, without nectary), free or slightly
connate at base, usually inserted at fleshy nectariferous disc.
Nectariferous disc usually present below petals and stamens,
often annular (rarely intrastaminal and/or extrastaminal, in
Reaumuria absent).

Androecium
Stamens in Myricaria 5+5 (antesepalous longer than
antepetalous), in Tamarix and Myrtama four or
five (to 14), in Reaumuria five to more than twelve
(from ten primordia). Filaments usually connate at base, usually
in a single group (in Reaumuria often five antepetalous
groups), sometimes free, usually inserted on fleshy nectariferous
disc, free from tepals. Anthers dorsifixed, versatile?,
tetrasporangiate, introrse, latrorse or extrorse, longicidal
(dehiscing by longitudinal slits). Tapetum secretory. Staminodia
absent.

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